/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2008 Erwin Coumans  http://bulletphysics.com

This software is provided 'as-is', without any express or implied warranty.
In no event will the authors be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software for any purpose, 
including commercial applications, and to alter it and redistribute it freely, 
subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/

#ifndef CHARACTER_CONTROLLER2_H
#define CHARACTER_CONTROLLER2_H

#include "LinearMath/btVector3.h"

#include "btCharacterControllerInterface.h"

#include "BulletCollision/BroadphaseCollision/btCollisionAlgorithm.h"


class btCollisionShape;
class btRigidBody;
class btCollisionWorld;
class btCollisionDispatcher;
class btPairCachingGhostObject;

/*-----------------------------------------------------------------------------
	btKinematicCharacterController is an object that 
	supports a sliding motion in a world.
	It uses a ghost object and convex sweep test to test for upcoming collisions. 
	This is combined with discrete collision detection to recover from penetrations.
	Interaction between btKinematicCharacterController and dynamic rigid bodies 
	needs to be explicity implemented by the user.
-----------------------------------------------------------------------------*/

class btCharacterController2 : public btActionInterface {
	public:
						btCharacterController2		( btPairCachingGhostObject* ghostObject,btConvexShape* convexShape,btScalar stepHeight, int upAxis = 1 );
						~btCharacterController2		( void );
		

		virtual void	updateAction				( btCollisionWorld* collisionWorld,btScalar deltaTime );
		void			debugDraw					( btIDebugDraw* debugDrawer );
		void			setUpAxis					( int axis );
		virtual void	setWalkDirection			( const btVector3& walkDirection );
		virtual void	setVelocityForTimeInterval	( const btVector3& velocity, btScalar timeInterval );
		void			reset						( void );
		void			warp						( const btVector3& origin );
		void			preStep						( btCollisionWorld* collisionWorld );
		void			playerStep					( btCollisionWorld* collisionWorld, btScalar dt );
		void			setFallSpeed				( btScalar fallSpeed );
		void			setJumpSpeed				( btScalar jumpSpeed );
		void			setMaxJumpHeight			( btScalar maxJumpHeight );
		bool			canJump						( void ) const;
		void			jump						( void );
		void			setUseGhostSweepTest		( bool useGhostObjectSweepTest );
		bool			onGround					( void ) const;

		btPairCachingGhostObject*	getGhostObject	( void );
		
	protected:

		btScalar			m_halfHeight;
		
		btPairCachingGhostObject* m_ghostObject;
		btConvexShape	*	m_convexShape;//is also in m_ghostObject, but it needs to be convex, so we store it here to avoid upcast
		
		btScalar			m_fallSpeed;
		btScalar			m_jumpSpeed;
		btScalar			m_maxJumpHeight;

		btScalar			m_turnAngle;
		
		btScalar			m_stepHeight;

		btScalar			m_addedMargin;//@todo: remove this and fix the code

		///this is the desired walk direction, set by the user
		btVector3			m_walkDirection;
		btVector3			m_normalizedDirection;

		//some internal variables
		btVector3			m_currentPosition;
		btScalar			m_currentStepOffset;
		btVector3			m_targetPosition;

		///keep track of the contact manifolds
		btManifoldArray		m_manifoldArray;

		bool				m_touchingContact;
		btVector3			m_touchingNormal;

		bool				m_useGhostObjectSweepTest;
		bool				m_useWalkDirection;
		btScalar			m_velocityTimeInterval;
		int					m_upAxis;

		static btVector3	* getUpAxisDirections();

		btVector3			computeReflectionDirection	( const btVector3& direction, const btVector3& normal );
		btVector3			parallelComponent			( const btVector3& direction, const btVector3& normal );
		btVector3			perpindicularComponent		( const btVector3& direction, const btVector3& normal );

		bool				recoverFromPenetration		( btCollisionWorld* collisionWorld );
		void				stepUp						( btCollisionWorld* collisionWorld );
		void				updateTargetPositionBasedOnCollision (const btVector3& hit_normal, btScalar tangentMag = btScalar(0.0), btScalar normalMag = btScalar(1.0) );
		void				stepForwardAndStrafe		( btCollisionWorld* collisionWorld, const btVector3& walkMove );
		void				stepDown					( btCollisionWorld* collisionWorld, btScalar dt );
	};

#endif // KINEMATIC_CHARACTER_CONTROLLER_H
